This invention relates to a cartridge including the operating mechanisms for a hydraulic equipment unit, and to a process for its instrumental assembly.
Many hydraulic equipment units are currently built in the form of bodies intended to receive, inserted therein, a cartridge containing all of the operating mechanisms for the apparatus or a great part of them. This manner of proceeding has proved to be suitable for facilitating and economizing the operations involved in control, maintenance, repair, and replacement of mechanisms of the hydraulic apparatus. According to the current state of the art, a cartridge for a hydraulic equipment unit comprises, as flow control members, a pair of plates made of hard material, provided with suitably shaped and cooperating passages, one of which plates is operatively fixed and is supported by a bottom member, while the other one is mobile and is connected to a guide and movement slide which, in turn, is connected to the operating means.
An important problem created by the production of cartridges, which usually entail a relatively large number of component parts, consists in the difficulty of achieving an entirely instrumental assembly of the component parts themselves, which would be desirable in order to reduce the costs and the long period of time needed for a total or partial manual assembly, as well as to ensure a high and uniform quality of the assembly that is done. These difficulties spring from the relatively large number of component parts, from the fact that some of them, such as the packings that are made of yielding material, present difficulties as regards instrumental handling, and by the fact that, considering the current structure of the cartridges, in most cases, the various component parts must be mutually connected by operating, in the case of some of the component parts, along different directions or in opposite senses, which considerably obstructs an instrumental assembly and, for executing the same, creates the need for complex, expensive apparatuses that are easily subjected to breakdown.